DHAKA (Reuters) - Bangladesh's war crimes tribunal sentenced a senior opposition leader to death on Tuesday in the seventh such verdict by the body set up to probe abuses during the country's bloody struggle for independence.

Salauddin Quader Chowdhury, a legislator from the Bangladesh Nationalist Party (BNP), was found guilty of torture, rape and genocide during the war for independence from Pakistan in 1971.

The verdict prompted calls for a strike in Chowdhury's home town of Chittagong and a van was set on fire in the capital, Dhaka.

The process has been denounced by opposition parties as politically motivated ahead of polls due by January and more than 100 people have been killed in protests against the war crimes verdicts since the start of this year. Six similar cases are pending.

Chowdhury, 64, was charged with killing 200 civilians and collaborating with Pakistan's army to kill and torture unarmed people, as well as other crimes during Bangladesh's nine-month fight for independence that ended in 1971.

The defence said it would appeal. None of the people sentenced so far has been executed.

Prime Minister Sheikh Hasina set up the tribunal in 2010 to probe abuses during the independence war that claimed about 3 million lives and during which thousands of women were raped.

The New York-based Human Rights Watch group has said the tribunal's procedures fall short of international standards. Critics say it is also being used by the prime minister to gut the two biggest opposition parties, the BNP and Jamaat-e-Islami.

(Reporting By Serajul Quadir; Editing by David Chance and Nick Macfie)